Cadet-Designed Trailer Could Power Deployments

U.S. AIR FORCE ACADEMY, Colo. -- A cadet capstone project designed to build upon cadets' research in 2012 could have broad-ranging applications from powering austere bases to supplementing stateside bases' power grids, instructors in the computer and electrical engineering department here said recently.
The project, a solar- and wind-powered all-terrain trailer, or SWATT, hooks up to a cadet-built electric dune buggy made last year and can provide a full charge of energy and the vehicle to other appliances.
"This is actually one of the better capstones that I've seen over the past several years," said Al Mundy, an instructor in the department. "The cadets' learning curve never stopped growing throughout the entire two semesters."
The cadets who worked on the project graduated May 29. They are 2nd Lts. Ben Baumann, Wes Cobb, Ryan Decarlis, Zane Dydasco, Alexandra Goodwin, Justin Juedemann, Stephen Katrein and William Petersen.

The trailer has roughly 200 cubic feet of space. Inside sits an 18-kilowatt-hour battery array that can power the vehicle or any device that can plug into a 110-volt wall outlet. The trailer can be charged via a wall outlet, a set of solar panels or a portable wind turbine designed by Class of 2010 cadets.

"They're not as fast as charging with the wall (outlet), but over the course of an eight-hour day or a 10-hour day, you can do relatively well," Mundy said.

A netbook computer plugged into the system monitors the battery level and ambient temperature, explained Dr. Tobi Moser, an exchange instructor from Germany.
"When they are full, it will shut off the charging system," Moser said. "You can deploy it somewhere, attach the solar panel and attach the wind turbine, and the rest will be done by the battery management system."
A cellphone hooked into the system allows it to send a text message in response to a query or if the temperature inside the trailer gets too hot, Mundy said.
The system is scalable, Mundy said, so a series of trailers could provide green power for a fleet of electric vehicles or replace the fuel bladders now ubiquitous in deployed environments.
"One of the things we'd like to do is have this be a modular part of deployed operation micro grids, i.e., plug it into the micro grid, and it helps offset diesel cost," said Lt. Col. Andrew Laffely, the department's assistant professor. "But this is a prototype, and we still have some work to do."
In the meantime, the green energy research has helped inspire interest in science, technology, engineering and mathematics, Laffely said.

"We are all focused on making our projects available to the public: going to public schools, supporting tours here ... to raise awareness of STEM, especially with school-age children," he said. "I think over the last year we've had more than 500 students from the local area have some sort of hands-on project with our lab and the vehicle staff."
In addition, the cadets who worked on the project will have more in-depth knowledge of future years' energy projects, Mundy said.
"I think this kind of project's really helped prepare them for when they're out there ... and the boss says, 'I need someone to talk to this electric vehicle company and have a clue what they're talking about,'" he said. "These are the kinds of things that they're going to be seeing in the next 20 years."